Electric Vehicles (EVs) are growing in popularity for reasons such as a different driving experience, higher performance, better reliability and lower maintenance, lower operational cost, and the potential to decrease the environmental impact of transportation. Electricity is used exclusively to propel the vehicle, or can be used to assist other methods such as internal combustion engines (ICEs).
The main types of the EVs are battery electric vehicles (BEV), plug-in hybrid electric vehicles (PHEV) and hybrid electric vehicles (HEV). EVs use an electric motor for propulsion. Electric energy is stored in batteries using, e.g. lithium-ion technology or any other form of battery chemistry. Other forms of energy storage are applicable too, such as supercapacitors or fuel cells. The HEV and the PHEV combine a conventional combustion engine with an electric drive system. HEVs use typically regenerative breaking to charge the batteries. PHEV contains rechargeable batteries that can be fully charged by connecting a plug to an external electric power source. BEVs are all electric vehicles without an internal combustion engine. The BEV and the PHEV also allows a user to choose alternative energy for charging the batteries by choosing external power source which is using for example a solar or wind power to produce electricity.
A common problem with current PHEVs and BEVs using rechargeable batteries is the charging time. In a typical case charging requires hours and there are also a lot of city center apartments without any plug-in capabilities for vehicles. There are also fast charging stations but also at these charging times are much longer compared with cars using combustion engines which can be quickly “charged” in fuel stations. Fast charging also means that batteries tend to wear out faster. Also energy density is not so high which means bigger and heavier batteries. Power losses are also higher with fast charging. Also charging an 80 kWh battery in for example 30 minutes sets such high power requirements that it is not possible typically at a residential home.
Another problem is that fast charging sets extra requirements for an electric infrastructure which is already stretched to the limit in many countries. In many industrialized nations, spare capacity in the order of magnitude of 50% or more, is periodically available and predictable. However, these are also times of lowest human and economic activity, which would be when fast charging is of no use. Although a typical user would charge at home during night time, a user could still prefer sourcing his energy from a commercial station which might offer lower prices than available to residential users. Other options include positive discrimination of renewable energies. For these cases current charging times are not what users are expecting.
There are several different proposals for changing the batteries for BEVs to overcome the problems described above. Typically, rechargeable cells are grouped as modules and each module consists of a plurality of cells. These modules are monitored and controlled as one entity. If needed, a module can be changed in service station to another module containing charged cells to supply quickly energy for BEV. One issue is that the available size for the battery varies a lot of depending on the use case and it might not be rectangular; one module doesn't fit well to all the use cases. It is possible to have modules with different size and form depending on the use case, meaning service stations should have stock of different modules also which do not make sense financially.
Examples of modular energy storage systems of the kind described above are disclosed in U.S. Pat. No. 7,948,207 and US 2012/094162. There are also many multicell battery designs available having the possibility to connect on and off individual cells of the battery. Examples of this kind of designs are disclosed in CN 202535104, CN 102832646, U.S. Pat. No. 8,330,420 and U.S. Pat. No. 7,075,194.
There are also several proposals as to how to monitor individual cells and how to use the characteristics of individual cells to configure a system dynamically. For example US 2010/0261043 proposes a system for dynamically reconfigurable battery framework for a large-scale battery system. This solves a problem how individual cells can be monitored and controlled but this system does not fit if the requirement is to replace hundreds of the depleted cells quickly in service station to supply electric energy for BEVs since the cells are located in certain way in a battery pack. Other control, failure-detection, reconfiguration, bypass and lifecycle management systems for batteries are disclosed for example in US 2005/242776, US 2006/192529, EP 2582009 and U.S. Pat. No. 8,084,994. These systems suffer at least partly from the same disadvantages.
Thus, there is a need for improved solutions for quickly supplying electric energy to electric vehicles and other power-intensive battery-operated devices.
US 2003/135705 discloses a programmable battery unit for portable computers. The battery unit is provided with a data word which is used to prevent inadvertent modification of the battery unit. In more detail, the memory contains a non-reprogrammable memory portion for the data word and a programmable memory portion. Checksum routines between the memory portions are used to check that the changes in the programmable memory are proper. There may be additional security measures using encryption and decryption of data. The reprogrammable memory may contain battery behaviour code related to charging and discharging the battery unit.
US 2009/309540 discloses a programmable vehicle battery capable of receiving data at a point of sale and point of maintenance and communicating this data to a centralized data network for warranty and metrics tracking purposes. The battery may contain multiple configurations, one of which is activated at the time of sale of the battery. In another embodiment, the battery is activated from a dormant state at the time of sale. At maintenance, various pieces of data can be entered into the battery and also communicated via a network to a database for storage or the battery can be diagnosed by reading the data and potentially comparing with the data in the database.
US 2012/0046015 discloses a smart mobile battery which can be authenticated by another device by using a private key securely located in the memory of the smart battery using a cryptographic challenge-response protocol. Using this method, the authenticity of the battery can be verified.
There are also many solutions concerning smooth battery exchange to battery-operated devices. For example US 2012/326665 discloses a method for quickly supplying energy to an electric vehicle. The method comprises providing a rechargeable battery pack on an electric vehicle and providing a battery replacement device, a charging room and a battery storeroom in a power exchange station. The rechargeable battery pack includes a battery box and standardized standard battery units loadable into and unloadable from the battery box along guiding rails when the electric vehicle in need of electric power supply is driven into the power exchanging station.
GB2353151 discloses an electrical vehicle driven by a cassette-type battery that can be freely installed into and removed from the electrical vehicle, and a battery storage location for the cassette-type batteries provided in proximity to the path of travel of the electrical vehicle. The user of the electrical vehicle can return the battery to the battery storage location and replaces it with a different cassette-type battery that has been charged from the battery storage location. In each of the cassette-type batteries, in addition to battery information, historical information about the charging condition is stored. Before and after charging the charging recorded of each battery is monitored, thereby enabling a judgment to be made with regard to the battery characteristics in order to find deteriorated batteries to be removed from the electrical vehicle energy supply system charging and supply system. The batteries may store information relating to the battery characteristics, their owner and have means for displaying this information.
The battery packs and cassettes discussed in the abovementioned document require very standardized receiving spaces for the batteries and have not received commercial success this far. Due to the strict mechanical constraints, the scalability of these systems is also low.
Despite the numerous battery designs already known, there are no such existing batteries or battery systems that would allow for used batteries to be easily traded at the point of refueling. Prior art solutions where batteries are swapped out during refueling either assume that the batteries are leased from a service provider, or do not consider the issue of the physical cost of the battery, and the deterioration in cost due to wear. As a result, they do not provide an acceptable solution where a transfer of ownership of the battery units themselves is involved, e.g. when a customer who owns the batteries in their car wishes to exchange the batteries for charged batteries in a charging station, owned by a battery provider. Since the cost of the batteries is much higher than the cost of the energy stored, the battery provider cannot simply charge for the energy in the batteries as if the new and old batteries were equivalent.